The investigators of this shared instrument grant are requesting a Meridian ACAS 470 for a variety of proposed projects related to their current funded research projects, including NIH grants. These investigators represent the disciplines of genetics, cell biology, biochemistry, immunology, physiology, biophysics and oncology. The instrument, the Meridian ACAS 470 workstation, is a unique instrument that integrates an inverted microscope with a computer-controlled, 0.5 Mum stepsize, X-Y motorized stage with argon laser with tunable UV and visible wavelengths and a photomultiplier tube. The computer system contains programs for computer analysis of images and data collected by the photomultiplier. The instrument has many applications, most yet undeveloped. Two general capabilities of the instrument are laser micro surgery and quantitative fluorescence analysis techniques on a single cell basis, for both living or fixed cells. These two capabilities are integrated into one of the instrument's function, cell sorting of anchored cells by either killing fluorescently tagged cells or conversely killing all but fluorescently tagged cells. The instrument is also capable of fluorescent recovery after photobleaching (FRAP) analysis of cells, computer generation of false color image (different color code for different fluorescent intensity) of fluorescent cells and laser microsurgery or any anchored cell. Proposed projects to determine (1) cell cycles of individual cells in a heterogenous population; (2) DNA damage repair in single cells; (3) role of tumor compression of cytoskeleton during neurite outgrowth; (4) to measure intracellular Ca++ on a single cell basis in living cells in response to variety of physiologic, pharmacologic and toxicologic stimuli; (5) response of living cells to growth regulatory factors; (6) the intracellular calcium concentrations in adherent platelets; (7) mechanism of natural killer cell binding to and killing of target cells; (8) the intracellular function of specific carnitine acyltransferases in liver cells; (9) the interaction between NK and macrophages in the killing of tumor cells; and (10) to assess, quantitatively, environmental pollutants ability to measure intercellular communication.